含钪铝锌镁合金铸锭和均匀化显微组织研究  

Investigation on Microstructure of As-cast and Homogenized Al-Zn-Mg-Sc Alloys

作　　者：李晨[1] 潘清林[1] 彭虹[2] 李波[1] 尹志民[1] 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083 [2]武汉职业技术学院,湖北武汉430074

出　　处：《热加工工艺》2012年第24期91-94,共4页Hot Working Technology

摘　　要：采用金相显微镜、差示扫描量热仪、扫描电镜及其能谱仪研究了Al-5.4Zn-2.0Mg-0.3Mn-0.25Cu-0.1Zr和Al-5.4Zn-2.0Mg-0.3Mn-0.35Cu-0.1Zr-0.25Sc两种合金的铸态及均匀化态显微组织演变与成分分布。结果表明:铸态组织以典型的枝晶结构存在,由过饱和的α-Al固溶体和α-Al+η-MgZn2的非平衡共晶相组成;铸态合金在470℃保温24 h,非平衡共晶相消失,合金枝晶偏析消除。确定合金铸锭的理想均匀化工艺参数为470℃×24 h。The microstructure evolution and composition distribution in the as-cast and homogenized state A1-5.4Zn- 2.0Mg-0.3Mn-0.25Cu-0.1Zr and A1-5.4Zn-2.0Mg-0.3Mn-0.35Cu-0.1Zr-0.25Sc aluminum alloy were investigated by OM, DSC, SEM and EDS. The results show that severe dendritic segregations exist in alloy ingot, and the as-cast microstructure of the alloys mainly consists of η-MgZn2 phase and et-A1 matrix. The eutectic morphology of precipitates and the interdendritic segregation disappears after homogenized treatment at 470℃ for 24 h. The appropriate homogenized treatment processing is determined to be 470℃ for 24 h.

关 键 词：含钪铝锌镁合金 均匀化处理 显微组织 η-MgZn2相 

分 类 号：TG146.2[一般工业技术—材料科学与工程]